Resolve safari not checking vault timeout every 10s (#1615)

src/services/vaultTimeout.service.ts

@@ -0,0 +1,28 @@
+import { VaultTimeoutService as BaseVaultTimeoutService } from 'jslib/services/vaultTimeout.service';
+import { SafariApp } from '../browser/safariApp';
+
+export default class VaultTimeoutService extends BaseVaultTimeoutService {
+
+    startCheck() {
+        this.checkVaultTimeout();
+        if (this.platformUtilsService.isSafari()) {
+            this.checkSafari();
+        } else {
+            setInterval(() => this.checkVaultTimeout(), 10 * 1000); // check every 10 seconds
+        }
+    }
+
+    // This is a work-around to safari adding an arbitary delay to setTimeout and
+    //  setIntervals. It works by calling the native extension which sleeps for 10s,
+    //  efficiently replicating setInterval.
+    async checkSafari() {
+        while(true) {
+            try {
+                await SafariApp.sendMessageToApp('sleep');
+                this.checkVaultTimeout();
+            } catch(e) {
+                console.log("Exception Safari VaultTimeout", e);
+            }
+        }
+    }
+}